In Europe, many rivers have been subject to human impacts, which can adversely affect aquatic biota and can result in a loss of ecosystem services. River restoration can alleviate unwanted impacts, but these projects are often expensive. Therefore, it is important to ensure an effective use of resources. This requires us to formulate clearly defined, quantifiable objectives that enable us to predict the outcome of different restoration measures. Ultimate aim of such a systematic procedure is to support decision makers to make an informed and best possible choice among different restoration alternatives.
Eawag is involved in transdisciplinary river restoration research since many years. Multi-Criteria Decision Analysis (MCDA) is a very suitable approach to support prioritizing river rehabilitation measures. MCDA allows a standardized integration of the assessment of the current ecological state, the prediction of the consequences of rehabilitation, and the preferences of stakeholders and experts concerning the objectives they aim at achieving.
A number of projects related to decision support for river rehabilitation and river management have been carried out at Eawag, primarily in the Siam department (see environmental decision support and model-based decision support ). Recent work includes the standardization of assessment procedures based on MCDA-principles (e.g. concerning aggregation of different indicators), the validity of common simplifications in MCDA (e.g. linear value functions, additive aggregation), and the conceptual foundation of environmental decision support (see publications).